Communication is one of the four public protection procedures Martyn’s Law requires, under section 5(3)(d) of the Act. Its purpose is “to ensure information is provided to people at the premises or event, alerting them to danger as quickly as possible if an attack is taking place” (statutory guidance, para. 7.46). Like the other three procedures, it must be in place “so far as is reasonably practicable” (para. 7.4).
Source: Terrorism (Protection of Premises) Act 2025: statutory guidance, Home Office, published 15 April 2026 and last updated 18 May 2026.
The four procedures, and where communication sits
The Act sets out four public protection procedures: evacuation (s.5(3)(a)), invacuation (s.5(3)(b)), lockdown (s.5(3)(c)) and communication (s.5(3)(d)). The guidance defines the fourth as “the process of ensuring information is provided to individuals at the premises or event (for example, alerting people to danger as quickly as possible and providing instructions to remain in place or move away, where it is safe to do so)”.
You do not need a separate set of procedures for every attack method. Para. 7.15 is explicit: the Act “does not mandate different versions of evacuation, invacuation, lockdown and communication procedures for each terrorist attack method”.
Why communication carries the other three
This is the part that tends to be underestimated. Para. 7.47 opens: “Effective communication with those on the premises or at the event is essential to enable the other procedures to be started quickly, reducing the risk of harm to people.”
An evacuation is a communication event before it is a movement event. So is a lockdown. The guidance makes the dependency concrete in para. 7.28: “a communication procedure (such as an announcement made via a public address system) may be used to alert people that a lockdown procedure should be followed”. And in the lockdown considerations: “a lockdown may be preceded by a communication procedure to ensure people present at the premises or event have been moved away from danger before the lockdown is started”.
Put plainly: three of your four procedures fail quietly if the fourth does not reach people.
What every responsible person must consider
Para. 7.48 sets out four considerations that apply to premises and events of any size. Working through them honestly is most of the job:
- “What information should be communicated, both to members of the public and to staff at the premises, as this information might differ. Information should be simple and clear to ensure any instructions are easy to understand and should be specific to the actions required to follow the relevant procedure.”
- “Who will share information when activating a procedure and who needs to be informed at the premises or event, and in the immediate vicinity if appropriate. This includes how staff will communicate with each other and how information will flow between staff and decision-makers.”
- “How to quickly share information in the way that works best for the premises or event.”
- “How to embed communication channels, processes, and roles and responsibilities prior to needing to use them. This could be achieved by documenting procedures, briefing staff and testing the communication procedure to ensure effectiveness and that staff are alert.”
The fourth is the one most often skipped. A channel that has never been used before the day it is needed is not a procedure; it is an assumption.
What larger and more complex sites must also consider
Para. 7.49 adds three considerations for “larger and more complex premises or qualifying events”:
- “Where people may be located when information is communicated and whether information will reach them effectively in those areas.”
- “How each procedure will be communicated effectively. For example, the instructions communicated for an evacuation procedure should be different to the instructions communicated for a lockdown procedure.”
- “How the communication procedure could be used without activating another procedure – for example, to encourage general awareness of suspicious activity or to give instructions related to measures like bag checks.”
That third point deserves attention, because it is the one that turns a plan into a practised capability. A channel used daily for ordinary instructions — which gate, which queue, which route — is a channel whose reach is known and whose audience is already conditioned to look at it. A channel reserved for emergencies is tested for the first time during one.
What the guidance names as means — and what it does not
The guidance is specific about methods. Para. 7.47: “Communication can take many forms, including verbal communication, signage, posters, briefings and audio broadcasts.” Para. 7.48 goes further: “public address systems, loud hailers/megaphones, closed radio systems and alarms could be used at larger premises or events, and more basic forms of alert such as giving loud, clear verbal commands could be used at smaller premises.”
Two things follow, and both matter when you are being sold to.
First, every item on that list is offered as an option — “could be used” — not an instruction. Para. 7.25 is unambiguous that there is “no statutory requirement in the Act to make any physical alterations or to purchase specific equipment relating to putting public protection procedures in place”. We have set that out in full in does Martyn’s Law require you to buy equipment?
Second, screens are not on the list. Neither are apps, nor text alerts. If anyone tells you the guidance calls for their category of product, ask for the paragraph number. There isn’t one.
What the guidance does instead is set a test rather than a specification. Para. 7.49 asks where people will be and “whether information will reach them effectively in those areas”. A public address system answers that well in a hotel lobby. It answers it less well across a campsite at night, on a stadium concourse at full capacity, or along a route where the crowd is moving and the ambient noise is louder than the announcement. The Act leaves it to you to work out which situation you are in.
Standard tier or enhanced tier: what actually differs
The communication procedure itself does not change between tiers. Para. 8.3 explains that the additional expectations for larger sites “are clearly noted within the considerations in chapter 7” — that is, the three points in para. 7.49 above.
What changes is everything around it. Enhanced tier premises and qualifying events must also put public protection measures in place under section 6, document their procedures and measures under section 7, and — if the responsible person is an organisation rather than an individual — designate a senior individual responsible for compliance under section 10. Para. 8.61 sets out what that document must contain: statements covering “how and when they will be used, and who can make relevant decisions in relation to the procedures or measures were an attack to occur”.
One asymmetry worth knowing: para. 8.5 notes that the Act does not require procedures under section 5 to be kept under review, although it is strongly recommended, whereas measures under section 6 must be. In practice the guidance advises reviewing both.
What “reasonably practicable” means in this context
Para. 7.21 splits the duty in two. “‘Appropriate’ means ensuring procedures are suitable, taking account of the context of the premises or event and avoiding a one-size-fits-all approach.” Only then do you ask how far it is reasonably practicable to go.
Para. 7.23 explains the second half: consider “the specific circumstances and nature of the qualifying premises or event, including the resources available to them”, weighing the objective of reducing physical harm against “the cost, time and difficulty”. It is a proportionality test, not a budget threshold — and it cuts both ways. A large, well-resourced venue cannot use the same reasoning as a 300-capacity restaurant.
Where CrowdCows fits, and where we do not
We build a system for one specific version of the para. 7.49 problem: places where reaching people is genuinely difficult. Screen content grounded in behavioural research, HIKER units placed where decisions get made, an independent broadcast signal that does not depend on mobile networks, a controller and an operator in the control room. It is used every day of an event for ordinary instructions, which is what makes its reach a known quantity rather than a hope.
It is not required by the Act, and we will not tell you otherwise. If your honest answer to the first question in para. 7.49 is that your existing channels already reach everyone, you do not need us. See how it worked at the British Grand Prix and Notting Hill Carnival, or read the wider Martyn’s Law overview.
For the situations a plan should cover in practice, see which scenarios your crowd communication should cover.
Frequently asked questions
What is the communication procedure under Martyn’s Law?
It is one of four public protection procedures required by section 5(3)(d) of the Terrorism (Protection of Premises) Act 2025. Para. 7.46 of the statutory guidance defines its purpose as ensuring information is provided to people at the premises or event, alerting them to danger as quickly as possible if an attack is taking place, and providing instructions where it is safe to do so.
Does the communication procedure differ between standard and enhanced tier?
The procedure itself does not. Para. 8.3 states that the additional expectations for larger and more complex sites are noted within the chapter 7 considerations — specifically the three points in para. 7.49. What differs is the surrounding duties: enhanced tier premises and qualifying events must also have public protection measures, document procedures and measures, and designate a senior individual for compliance.
What means of communication does the guidance recommend?
Para. 7.47 mentions verbal communication, signage, posters, briefings and audio broadcasts. Para. 7.48 adds that public address systems, loud hailers or megaphones, closed radio systems and alarms could be used at larger premises or events, and that loud, clear verbal commands could be used at smaller ones. All are presented as options rather than requirements, and the guidance does not name screens, apps or text alerts.
Does communication have to be linked to the other procedures?
In practice, yes. Para. 7.47 states that effective communication is essential to enable the other procedures to be started quickly. Para. 7.28 gives the example of a public address announcement used to alert people that a lockdown procedure should be followed.
Do I need a different communication procedure for each attack type?
No. Para. 7.15 states that the Act does not mandate different versions of the procedures for each terrorist attack method, although it notes that certain procedures may be more effective than others depending on the nature of the attack.
Do procedures have to be reviewed?
Para. 8.5 notes that the Act does not require public protection procedures under section 5 to be kept under review, although this is strongly recommended. Public protection measures under section 6 must be kept under review by the responsible person for enhanced tier premises. The guidance advises reviewing both, periodically and possibly annually depending on circumstances.
Last reviewed 29 July 2026 against the statutory guidance published 15 April 2026 (updated 18 May 2026). This page explains published government guidance. It is not legal advice, and only the SIA determines compliance. The legal responsibility for procedures rests with the responsible person and cannot be delegated to a contractor (para. 6.1).
